This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We propose to conduct a proof-of-concept investigation in 3 healthy adults who would receive 13C-U-tyrosine by vein before and after 5 days of 12.5 mg/kg/bid DCA, the typical clinical dose and dose schedule. We will determine tyrosine kinetics by standard kinetic modeling techniques we have employed previously and by GC/MS and LC/MS methods we have developed to identify and quantify both tyrosine and DCA and their metabolites.